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This article will explore the methods of specifying unique constraints for multiple columns in MySQL. Specifying unique constraints for multiple columns in MySQL You may sometimes want to guarantee that every value in a column or set of col...

In this article, we will learn how to add an auto-increment column in MySQL. Adding an auto-increment column in MySQL When creating a table, we may not have a unique identifier in the database, which brings problems to choosing the primary...

In MySQL or any programming language, there are privileges to add constraints or checks in the instance of creating a table. These constraints help the user to restrict the values ​​inserted into specific fields of the table. The restri...

In this article, we will learn to update multiple columns with different values ​​in multiple rows in MySQL using CASE statement, IF() function, INSERT ... ON DUPLICATE KEY UPDATE clause and function. UPDATE with JOIN() Update multiple...

This article describes how to use SQL query to obtain the data records of the last 30 days from the database. Import data into the database First, let's import some sample data into the database using SQL query. Before we import the dataset...

Today, we will learn the DATE(), CAST(), CONVERT() and DATE_FORMAT() methods to convert DATETIME type to DATE type in MySQL. The above mentioned methods can be used in MySQL 4.0 and above. Converting from DATETIME to DATE in MySQL To unders...

This article describes how to simulate a foreach loop in MySQL using INSERT, SELECT, WHERE, and JOIN in one statement. MySQL foreach loop To understand foreach loop simulation, let us create three tables with the following names and attribu...

In this article, we will learn how to sum multiple columns in MySQL. Sum multiple columns in MySQL You can use aggregate functions SUM() to calculate the total value in a collection. SUM() The function calculation does not consider NULL val...

In this article, we will introduce many ways to check if a database exists in MySQL. Check if the database exists in MySQL The system schema is the schema that MySQL uses. It includes tables that contain data needed by a running MySQL serve...

This article focuses on the various queries that can be used to display the current database in MySQL. We will learn by using the Windows command line and MySQL Workbench. Display the current database in MySQL We can use the following query...

In this article, we will learn about various ways to sort data alphabetically in MySQL. Sort MySQL data alphabetically When you use the SELECT command to query data from a table, the rows in the result set are in arbitrary order. To order t...

In this article, we will learn how to find the difference between two tables in MySQL. The difference between two tables in MySQL We often need to compare two tables to find records in one table that have no matching records in the other ta...

Today, we will learn how to TIMESTAMP insert date and time into a type column of a MySQL table according to the table definition. Create a MySQL table First, we will create the tables that we will use in this tutorial. Sample code: CREATE T...

Today, we will explore three scenarios and their solutions where we want to select the first row from a MySQL table. In the first scenario, we will learn to get the first row from a MySQL table where there are multiple instances of a partic...

Today, we will learn about queries in MySQL that can display the table and database structure. We will use the mysqldump utility, DESCRIBE the , SHOW TABLES and SHOW CREATE TABLE the statements. We are using MySQL version 8.0.28 while writi...